Apparatus for automatically filling a predetermined amount of powdered grain substance

ABSTRACT

Apparatus for automatically filling a pre-determined amount of powdered granular material into a bag. The apparatus comprises a screw feeder provided within a tubular conveyor case, the walls of which are flexible. A smooth transfer of powder is effected by vibrating the walls of the conveyor case. In addition, to transfer the substance from the conveyor a pulsed compressed air stream is jetted at the substance being transferred near the other end of the conveyor case. Within the conveyor case are provided a mixing chamber, and a supply tube connected to measuring apparatus via a flexible tube, so that when a predetermined amount of powdered material is filled in the bag, the filling operation automatically comes to a stop.

Uitd States Patent 11 1 Nakashima APPARATUS FOR AUTOMATICALLY FILLING APIKE-DETERMINED AMOUNT OF POWDERED GRAIN SUBSTANCE 1mm L 2i 5 m -la gaarn;

jinmori, Oaza Morimoto, komachi, Otokuni-gun, Kyoto-fu Japan Filed:Sept. 11, 1970 Appl. No.: 71,506

Foreign Application Priority Data Jan. 31, 1970 Japan ..45/8632 Nov.Japan ....44/91507 References Cited UNITED STATES PATENTS 1,593,5177/1926 Tharrington ..222/145 UX 2,065,079 12/1936 Lauterbur 2,260,30210/1941 Driscolletal. ..222/4l3 Primary Examiner-Robert B. ReevesAssistant Examiner-John P. Shannon Attorney-Kurt Kelman 57 ABSTRACTApparatus for automatically filling a pre-determined amount of powderedgranular material into a bag. The apparatus comprises a screw feederprovided within a tubular conveyor case, the walls of which areflexible. A smooth transfer of powder is effected by vibrating the wallsof the conveyor case. In addition, to transfer the substance from theconveyor a pulsed compressed air stream is jetted at the substance beingtransferred near the other end of the conveyor case. Within the conveyorcase are provided a mixing chamber, and a supply tube connected tomeasuring apparatus via a flexible tube, so that when a pre-determinedamount of powdered material is filled in the bag, the filling operationautomatically comes to a stop.

5 Claims, 4 Drawing Figures PATENTEDMARwsza sum 1 or 2 Fig. 1

INVENTOR. SHIGEO NAKAsHlMA KM WWW AGENT PAYENIEDw-Y 2713. 3 $722,755

SHEET 2 UF 2 IN VEN TOR.

APPARATUS FOR AUTOMATICALLY FILLING A PRIZE-DETERMINED AMOUNT OFPOWDERED GRAIN SUBSTANCE The present invention is related to anapparatus for automatically filling a pre-determined amount of powderedgrain substance.

More particularly the present invention is related to an apparatusessentially comprising a screw-feeder provided within a tubular conveyorcase,the walls of which are made of flexible tubes such as rubber sothat a smooth transfer of powdered grain substance after deairingprocessing is effected by means of screw feeder within the conveyorcase, the walls of the case being vibrated incessantly to transfer thesubstance without sticking to the walls, and the compressed air streamin pulses being jetted at the substance being transferred near the otherend of the conveyor case. Within the conveyor case are provided a mixingchamber in a shape of a trumpet, a supply tube connected to measuringportion via a flexible tube so that when a pre-determined amount ofpowdered grain substance is filled in a packing bag, the fillingoperation automatically comes to a stop.

The present invention is further described in relation to one embodimentthereof and reference being made to attached drawings in which;

FIG. 1 is an explanatory drawing of one embodiment of the presentinvention;

FIG. 2 is a cross-sectional view along lines AA of FIG. 1,

FIG. 3 is an enlarged view of the feeder part of FIG. 1, and

FIG. 4 is a cross-sectional view of the feeder part of anotherembodiment according to the present invention.

More in detail, the apparatus of the present invention comprises ahopper(1) de-airing means(2), the pressure feeding part(3) and measuringpart(4).

l. Hopper In FIG. 1, 1 is a tank tapered toward the semi-circular arcshaped bottom part 2, one side 3 of the bottom part being opened andconnected to a horizontal tubular screwconveyor case 4(hereinafterreferred to as a conveyor case). FIG. 2 is a cross-sectional view ofFIG. 1 along the line AA in which 5 denotes an agitating rod within thetank.

2. De-airing means De-airing means is shown in FIG. 1 by the dotted linewherein a separating chamber B is provided suitably inside the conveyorcase 4 connected to the bottom part 2 of the tank. The lower partthereof is opened to be connected to supply chamber outlet 6. A duct 7is provided at one end of the conveyor case 4 opened upwardly. 8 denotesa shaft for screw conveyors 9, 9', provided fixedly with screws for thedistance from bottom part 2 of the tank to the separating chamber B andfrom separating chamber B to one end 10 of the conveyor case 4, axiallyalong the shaft but in such a way that the facing screws move inopposite directions from each other. That is to say, the blades of theeach of conveyors 9, 9 are turned in the opposite direction. Screwconveyor 9 is pitched in a successive diminuition toward its end in thedirection of the separating chamber 13. ll, 11 denote bearings for theshaft 8 of the screw conveyor. 12, 13 respectively are chain wheelsfixed to the agitating rod 5 and to the shaft 8 of the screw conveyorand l4, 15 are also chain wheels fixed to the shaft 8 of the screwconveyor and a motor M. 16, 17 denote chains. The duct 7 is connected tothe open air either directly or via de-airing fan with a duct tube 19having a filter 18 connected to the end thereof.

3. The Pressure Feeding Part The pressure feeding part is shown in anenlarged explanatory view in FIG. 3 in which 20 is a pressure feedercase connected to the bottom part of the supply chamber outlet 6, 21 aninlet and 22 an outlet thereof respectively. A cylinder 23 made of asoft material and flanges 24, 24' 24, 24' supported by stay boards 38are connected to the side 39 of the transfer case 20 by bolts 40 in onebody, the tension of the cylinder 23 having been adjusted preliminarilyby nuts 41 at one ends of stay boards 38. A flange for the rigidcylindrical tube 25 provided in the center of the flange 24, a fillingtube 27 and a flexible tube 2 are connected to the end of the cylinder23. 28 is a hollow shaft with a nozzle 29 at one end. A screw feeder 30is provided through the compressure feeder case 20 and the cylinder 23on the outer circumference of the shaft and in a successive dimunitiontoward one end of the shaft, thereby forming a trumpet shaped mixingchamber 31 in the space at the end of the cylinder 23 and between theend of the shaft 28 and the cylindrical tube 25. Another end of theshaft 28(in the opposite direction of the nozzle 29) is supported by abearing 32 and is connected to the compressed air source(not shown inthe drawings). Pulley 33 fixed to the shaft 28 transmits rotation fromthe motor M via a belt 34 to rotate the screw feeder 30. 35 denoets aleg of the compression feeder case 20, 36 a support for the bearing 32and 37 a base respectively. 4. Measuring Part Measuring part consists ofa measuring apparatus 50 and a measuring frame 42 connected to the base37 by way of two parallel arms 41, 41 of the mechanism in such a way asto be freely movable in a vertical direction. The measuring apparatus 50and the upper face 43 of the measuring frame 42 are connected in a scalevia hanging rod 44. The filling tube 27 is connected through said frame42 with its base 45 fixed to frame in a body.

Now the present invention will be described referring to the operationand the effects thereof;

Powder grain substance poured into the tank 1 is fed uniformly to thescrew conveyor 9 provided at the base 2 by rotation of the agitating rod5. The powdered substance is fed forwardly toward the separating room Bwithin the transfer case 4 from the base 2 of the tank by rotatingconveyor 9.

Since the screw conveyor 9 is pitched in successive dimunition towardits end, the volume of the powdered substance as it proceeds with thetransfer case 4 is compressed, the air being pressed out, and reachesthe separating room B to be induced to the supply chamber outlet 6. Theair is lead through the separating chamber B, the transfer case 4 andde-airing duct through the filter 18 to the out of the apparatus. Insome cases, the air is forced out further through a duct tube 19 havingthe filter 18 at the end of the duct 7 by the fan P. When a part of thepowdered substance pressed into the separating room by the screwconveyor 9 within the transfer case 4 happens to go toward the screwconveyor 9 beyond the separating room B, the said part of the powderedsubstance is pushed back toward the separating chamber by the rotationof the screw conveyor 9' to be induced with the compressed powderedsubstance from the direction of screw conveyor 9. Thus the air streamfrom the separating chamber toward left is allowed to pass through theseparating room B while the stream of the powdered substance is pushedback into the separating room B by the rotation of the banks of theconveyor 9. The completely de-aired powdered substance is now guided tothe inlet 21 of the feed part from the supply chamber outlet 6.

The powdered grain substance is further transfered into the cylinder 23via the inlet 21 and the outlet 22 of the feeder case by the rotation ofthe screw feeder 30 provided in the bottom of the feeder case 20. Thevolume of the substance within the cylinder is compressed and changed bymeans of the screw feeder 30 pitched in successive diminution to betransferred to thefunnel shaped mixing chamber 31 at the end of thecylinder 23. The pow'dered substance is then admixed within said chamberby the compressed air stream being jetted from the nozzle 29 and filledto the bag 47 on the bag stand 46 fixedly provided at the bottom of themeasuring frame 42 via the cylinderical tube 25, the flexible tube 26and to the filling tube 27.

The weight of the filled bag falls on the measuring frame 42 and istransmitted to the measuring apparatus 50 via the hanging rod 44 with afine movement of the frame.

in the present invention, the compressed air stream is jetted from saidnozzle 29 intermittently in pulses in order to fill the bag with highdensity. in the conventional method, a mixture of air and solid wasjetted out of the filling tube at a high speed, whereas the presentinvention facilitates high density filling by the pulse movement of thecompressed air stream at a certain interval. Moreover, the pulsemovement of the compressed air stream presents a phenomenon wherein anair column in the space leading from the mixing chamber 31 the fillingtube 27 the bag 47 resonates with said pulse air current in jet to forma cavity, a separation or an exfoliation like a super sonic wave.Accordingly, the particles of the powdered grain substance never stickto the inner walls of the tube, the bag 47, etc. contacting with saidspaces, facilitating an efficient filling. This is the same effectobtained in the manual operation wherein the powder substances stickingto the inner side of the bag or the tube is beaten by sticks or given afine vibrating movement.

In the aforementioned case, when the powdered substance is pressedforwardly into the cylinder 23 by the use of the screw feeder 30 andfluidized, accelerated and pressurized by the jet stream of compressedair from the jet nozzle 29 for filling the bag 47, the powderedsubstance inclines to be pressed back in the screw feeder 30 and thecylinder 23 by the backpressure of the reaction. in order to press thepowdered substance in resistance to the back pressure, it is usuallycontrived to utilize the material seal effects in de-air state, that isto sufficiently compress the powdered substance in the cylinder 23 andto heighten the density thereof. However, material seal effect is notseen in the case when the powdered substance fed to the screw feeder 30is the substance containing air and having high fluidity, lowering thecompression effect of the screw feeder. This is generally known to becaused by the presence of air particles among the powdered substanceacting as a lubricant and deteriorating the compression effectiveness.This phenomenon becomes more remarkable as the density of the airbecomes higher, thereby increasing the filling hour and deterioratingwork efficiency in packing. It is, therefore, desirable for materialsealing by the screw feeder that the powdered substance to be suppliedto the screw feeder is de-aired and have a low air density. This isproceed by the effects seen in the instance wherein the substance whichhave been stocked in a silo for a set period of time and thus naturallyhave been de-aired is fed to the screw feeder The cycle of the pulse ofcompressed air stream, the width of the pulse are suitably arrangedtaking the physical factors of the powdered grain substance intoaccount.

The powdered substance reaches cylinder 23 from the outlet 22 of thefeeder case 20 and is compressedly fed forward within the cylinder 23made of soft materials such as antiabrasive rubber, fine siliconprocessed nylon net and tensioned by stay board 38.

The compressed powdered substance exerts its pressure on the innersurface of the cylinder 23 to expand and inflate the soft cylinder 23 sothat the cylinder vibrates itself, and it moves forward along the spacebetween the screw feeder 30 and the inner surface of the cylinder 23.The result is that the powdered grain substance does not stick to theinner surface of the cylinder but moves forward efficiently.

The multiple effect of items (2), (3), namely the jetting of compressedair stream in pulses from the jet nozzle 29 of the hollow shaft 28 andthe rotation of the screw feeder in the cylinder 23 made of soft andflexible material, is that every kind of powdered substance can be fedforwardly smoothly and efficiently. This is I the most remarkablecharacteristic of the present invention which can be utilized intransfers of every kind of powdered substance,not being limited to theabove embodiment of feeding process of the powdered substance to anapparatus for automatically filling the predetermined amount into a bag.in the conventional type cylinders of metallic type, such stickypowdered grain substances as dextrose, alpha-dextrin, synthetic meatpowders and the like stick and pile between the screw feeder and theinner surface of the cylinder until the substance closes the cylinderand stops the rotation of the screw feeders very often.

Fluidizing, accelerating and pressurizing the powdered substance bysending the substance forward by the screw feeder 30 and jetting thecompressed air stream by the jet nozzle 29 in the mixing chamber 31,

automatic filling apparatus of a pre-determined amount into a bagwherein the screw feeder for compressed feeding characterized in theabove manner is given an efficient de-airing process with de-airingmeans 2 and it feeds the powdered substance to the bag 47 set on the bagstand 46 connected to the measuring apparatus 50 by the filling tube 27via flexible tube 26 connected to the cylinder 23.

When filling the bag with the powdered substance from the end of thefilling tube into the bag 47, the bag stand 46 and the filling tube 45are connected to the measuring apparatus 50.

The powdered substance is measured as it is being fed into the bag 47from the filling tube 27, which is inserted into and is contacting withthe filling hole 48 of the bag 47 on the bagstand 46. Further the tubeis connected to the cylinder 23 and the mixing chamber 31 via saidflexible tube 26. Thus, the accurate measuring is maintained in theapparatus for automatically filling a predetermined amount causing noerror in the measured amount.

What we claim is,

1. An apparatus for automatically bag filling a predetermined weightamount of powdered substance, said apparatus comprising in combination,a powdered substance supply hopper, de-airing means, said de-airingmeans having a first screw conveyor for transfer of powdered substancefrom said hopper to a discharge chamber, a second screw conveyoroppositely disposed to said chamber and having screw blades rotatingopposite said first screw conveyor for pushing powdered substance towardsaid chamber, and a de-airing duct for exhausting air from said firstconveyor, said first screw conveyor being pitched in successivedimunition toward its discharge end, pressure feeding means having screwfeeding means for receiving powered substance from the said chamber andfor transferring same to a tapered flexible mixing chamber, said screwfeeding means having a hollow shaft for transfer of pulses of compressedair to the mixing chamber, a weight measuring means comprising a weightindicator, a bag support in communication with said weight indicator,and a bag for receiving powdered substance by means of a dischargenozzle, said discharge nozzle being connected to said tapered flexiblemixing chamber by means ofa flexible tube.

2. The apparatus of claim 1, wherein means are included for maintainingthe walls of said mixing chamber under tension.

3. The apparatus of claim 1, wherein said screw feeding means is partlydisposed within the tapered flexible mixing chamber.

4. The apparatus of claim 1, wherein screw conveyors of the de-airingmeans are substantially horizontally disposed and are co-axially mountedon a shaft.

5. The apparatus of claim 1, wherein filter means are included in saidde-airing duct for exhausting air.

1. An apparatus for automatically bag filling a predeTermined weightamount of powdered substance, said apparatus comprising in combination,a powdered substance supply hopper, de-airing means, said de-airingmeans having a first screw conveyor for transfer of powdered substancefrom said hopper to a discharge chamber, a second screw conveyoroppositely disposed to said chamber and having screw blades rotatingopposite said first screw conveyor for pushing powdered substance towardsaid chamber, and a deairing duct for exhausting air from said firstconveyor, said first screw conveyor being pitched in successivedimunition toward its discharge end, pressure feeding means having screwfeeding means for receiving powered substance from the said chamber andfor transferring same to a tapered flexible mixing chamber, said screwfeeding means having a hollow shaft for transfer of pulses of compressedair to the mixing chamber, a weight measuring means comprising a weightindicator, a bag support in communication with said weight indicator,and a bag for receiving powdered substance by means of a dischargenozzle, said discharge nozzle being connected to said tapered flexiblemixing chamber by means of a flexible tube.
 2. The apparatus of claim 1,wherein means are included for maintaining the walls of said mixingchamber under tension.
 3. The apparatus of claim 1, wherein said screwfeeding means is partly disposed within the tapered flexible mixingchamber.
 4. The apparatus of claim 1, wherein screw conveyors of thede-airing means are substantially horizontally disposed and areco-axially mounted on a shaft.
 5. The apparatus of claim 1, whereinfilter means are included in said de-airing duct for exhausting air.